libstdc++
basic_string.tcc
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1// Components for manipulating sequences of characters -*- C++ -*-
2
3// Copyright (C) 1997-2023 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file bits/basic_string.tcc
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{string}
28 */
29
30//
31// ISO C++ 14882: 21 Strings library
32//
33
34// Written by Jason Merrill based upon the specification by Takanori Adachi
35// in ANSI X3J16/94-0013R2. Rewritten by Nathan Myers to ISO-14882.
36// Non-reference-counted implementation written by Paolo Carlini and
37// updated by Jonathan Wakely for ISO-14882-2011.
38
39#ifndef _BASIC_STRING_TCC
40#define _BASIC_STRING_TCC 1
41
42#pragma GCC system_header
43
44#include <bits/cxxabi_forced.h>
45
46namespace std _GLIBCXX_VISIBILITY(default)
47{
48_GLIBCXX_BEGIN_NAMESPACE_VERSION
49
50#if _GLIBCXX_USE_CXX11_ABI
51
52 template<typename _CharT, typename _Traits, typename _Alloc>
53 const typename basic_string<_CharT, _Traits, _Alloc>::size_type
55
56 template<typename _CharT, typename _Traits, typename _Alloc>
57 _GLIBCXX20_CONSTEXPR
58 void
60 swap(basic_string& __s) _GLIBCXX_NOEXCEPT
61 {
62 if (this == std::__addressof(__s))
63 return;
64
65 _Alloc_traits::_S_on_swap(_M_get_allocator(), __s._M_get_allocator());
66
67 if (_M_is_local())
68 if (__s._M_is_local())
69 {
70 if (length() && __s.length())
71 {
72 _CharT __tmp_data[_S_local_capacity + 1];
73 traits_type::copy(__tmp_data, __s._M_local_buf,
74 __s.length() + 1);
75 traits_type::copy(__s._M_local_buf, _M_local_buf,
76 length() + 1);
77 traits_type::copy(_M_local_buf, __tmp_data,
78 __s.length() + 1);
79 }
80 else if (__s.length())
81 {
82 _M_init_local_buf();
83 traits_type::copy(_M_local_buf, __s._M_local_buf,
84 __s.length() + 1);
85 _M_length(__s.length());
86 __s._M_set_length(0);
87 return;
88 }
89 else if (length())
90 {
91 __s._M_init_local_buf();
92 traits_type::copy(__s._M_local_buf, _M_local_buf,
93 length() + 1);
94 __s._M_length(length());
95 _M_set_length(0);
96 return;
97 }
98 }
99 else
100 {
101 const size_type __tmp_capacity = __s._M_allocated_capacity;
102 __s._M_init_local_buf();
103 traits_type::copy(__s._M_local_buf, _M_local_buf,
104 length() + 1);
105 _M_data(__s._M_data());
106 __s._M_data(__s._M_local_buf);
107 _M_capacity(__tmp_capacity);
108 }
109 else
110 {
111 const size_type __tmp_capacity = _M_allocated_capacity;
112 if (__s._M_is_local())
113 {
114 _M_init_local_buf();
115 traits_type::copy(_M_local_buf, __s._M_local_buf,
116 __s.length() + 1);
117 __s._M_data(_M_data());
118 _M_data(_M_local_buf);
119 }
120 else
121 {
122 pointer __tmp_ptr = _M_data();
123 _M_data(__s._M_data());
124 __s._M_data(__tmp_ptr);
125 _M_capacity(__s._M_allocated_capacity);
126 }
127 __s._M_capacity(__tmp_capacity);
128 }
129
130 const size_type __tmp_length = length();
131 _M_length(__s.length());
132 __s._M_length(__tmp_length);
133 }
134
135 template<typename _CharT, typename _Traits, typename _Alloc>
136 _GLIBCXX20_CONSTEXPR
137 typename basic_string<_CharT, _Traits, _Alloc>::pointer
138 basic_string<_CharT, _Traits, _Alloc>::
139 _M_create(size_type& __capacity, size_type __old_capacity)
140 {
141 // _GLIBCXX_RESOLVE_LIB_DEFECTS
142 // 83. String::npos vs. string::max_size()
143 if (__capacity > max_size())
144 std::__throw_length_error(__N("basic_string::_M_create"));
145
146 // The below implements an exponential growth policy, necessary to
147 // meet amortized linear time requirements of the library: see
148 // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
149 if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
150 {
151 __capacity = 2 * __old_capacity;
152 // Never allocate a string bigger than max_size.
153 if (__capacity > max_size())
154 __capacity = max_size();
155 }
156
157 // NB: Need an array of char_type[__capacity], plus a terminating
158 // null char_type() element.
159 return _S_allocate(_M_get_allocator(), __capacity + 1);
160 }
161
162 // NB: This is the special case for Input Iterators, used in
163 // istreambuf_iterators, etc.
164 // Input Iterators have a cost structure very different from
165 // pointers, calling for a different coding style.
166 template<typename _CharT, typename _Traits, typename _Alloc>
167 template<typename _InIterator>
168 _GLIBCXX20_CONSTEXPR
169 void
170 basic_string<_CharT, _Traits, _Alloc>::
171 _M_construct(_InIterator __beg, _InIterator __end,
173 {
174 size_type __len = 0;
175 size_type __capacity = size_type(_S_local_capacity);
176
177 _M_init_local_buf();
178
179 while (__beg != __end && __len < __capacity)
180 {
181 _M_local_buf[__len++] = *__beg;
182 ++__beg;
183 }
184
185 struct _Guard
186 {
187 _GLIBCXX20_CONSTEXPR
188 explicit _Guard(basic_string* __s) : _M_guarded(__s) { }
189
190 _GLIBCXX20_CONSTEXPR
191 ~_Guard() { if (_M_guarded) _M_guarded->_M_dispose(); }
192
193 basic_string* _M_guarded;
194 } __guard(this);
195
196 while (__beg != __end)
197 {
198 if (__len == __capacity)
199 {
200 // Allocate more space.
201 __capacity = __len + 1;
202 pointer __another = _M_create(__capacity, __len);
203 this->_S_copy(__another, _M_data(), __len);
204 _M_dispose();
205 _M_data(__another);
206 _M_capacity(__capacity);
207 }
208 traits_type::assign(_M_data()[__len++], *__beg);
209 ++__beg;
210 }
211
212 __guard._M_guarded = 0;
213
214 _M_set_length(__len);
215 }
216
217 template<typename _CharT, typename _Traits, typename _Alloc>
218 template<typename _InIterator>
219 _GLIBCXX20_CONSTEXPR
220 void
221 basic_string<_CharT, _Traits, _Alloc>::
222 _M_construct(_InIterator __beg, _InIterator __end,
224 {
225 size_type __dnew = static_cast<size_type>(std::distance(__beg, __end));
226
227 if (__dnew > size_type(_S_local_capacity))
228 {
229 _M_data(_M_create(__dnew, size_type(0)));
230 _M_capacity(__dnew);
231 }
232 else
233 _M_init_local_buf();
234
235 // Check for out_of_range and length_error exceptions.
236 struct _Guard
237 {
238 _GLIBCXX20_CONSTEXPR
239 explicit _Guard(basic_string* __s) : _M_guarded(__s) { }
240
241 _GLIBCXX20_CONSTEXPR
242 ~_Guard() { if (_M_guarded) _M_guarded->_M_dispose(); }
243
244 basic_string* _M_guarded;
245 } __guard(this);
246
247 this->_S_copy_chars(_M_data(), __beg, __end);
248
249 __guard._M_guarded = 0;
250
251 _M_set_length(__dnew);
252 }
253
254 template<typename _CharT, typename _Traits, typename _Alloc>
255 _GLIBCXX20_CONSTEXPR
256 void
257 basic_string<_CharT, _Traits, _Alloc>::
258 _M_construct(size_type __n, _CharT __c)
259 {
260 if (__n > size_type(_S_local_capacity))
261 {
262 _M_data(_M_create(__n, size_type(0)));
263 _M_capacity(__n);
264 }
265 else
266 _M_init_local_buf();
267
268 if (__n)
269 this->_S_assign(_M_data(), __n, __c);
270
271 _M_set_length(__n);
272 }
273
274 template<typename _CharT, typename _Traits, typename _Alloc>
275 _GLIBCXX20_CONSTEXPR
276 void
277 basic_string<_CharT, _Traits, _Alloc>::
278 _M_assign(const basic_string& __str)
279 {
280 if (this != std::__addressof(__str))
281 {
282 const size_type __rsize = __str.length();
283 const size_type __capacity = capacity();
284
285 if (__rsize > __capacity)
286 {
287 size_type __new_capacity = __rsize;
288 pointer __tmp = _M_create(__new_capacity, __capacity);
289 _M_dispose();
290 _M_data(__tmp);
291 _M_capacity(__new_capacity);
292 }
293
294 if (__rsize)
295 this->_S_copy(_M_data(), __str._M_data(), __rsize);
296
297 _M_set_length(__rsize);
298 }
299 }
300
301 template<typename _CharT, typename _Traits, typename _Alloc>
302 _GLIBCXX20_CONSTEXPR
303 void
305 reserve(size_type __res)
306 {
307 const size_type __capacity = capacity();
308 // _GLIBCXX_RESOLVE_LIB_DEFECTS
309 // 2968. Inconsistencies between basic_string reserve and
310 // vector/unordered_map/unordered_set reserve functions
311 // P0966 reserve should not shrink
312 if (__res <= __capacity)
313 return;
314
315 pointer __tmp = _M_create(__res, __capacity);
316 this->_S_copy(__tmp, _M_data(), length() + 1);
317 _M_dispose();
318 _M_data(__tmp);
319 _M_capacity(__res);
320 }
321
322 template<typename _CharT, typename _Traits, typename _Alloc>
323 _GLIBCXX20_CONSTEXPR
324 void
325 basic_string<_CharT, _Traits, _Alloc>::
326 _M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
327 size_type __len2)
328 {
329 const size_type __how_much = length() - __pos - __len1;
330
331 size_type __new_capacity = length() + __len2 - __len1;
332 pointer __r = _M_create(__new_capacity, capacity());
333
334 if (__pos)
335 this->_S_copy(__r, _M_data(), __pos);
336 if (__s && __len2)
337 this->_S_copy(__r + __pos, __s, __len2);
338 if (__how_much)
339 this->_S_copy(__r + __pos + __len2,
340 _M_data() + __pos + __len1, __how_much);
341
342 _M_dispose();
343 _M_data(__r);
344 _M_capacity(__new_capacity);
345 }
346
347 template<typename _CharT, typename _Traits, typename _Alloc>
348 _GLIBCXX20_CONSTEXPR
349 void
350 basic_string<_CharT, _Traits, _Alloc>::
351 _M_erase(size_type __pos, size_type __n)
352 {
353 const size_type __how_much = length() - __pos - __n;
354
355 if (__how_much && __n)
356 this->_S_move(_M_data() + __pos, _M_data() + __pos + __n, __how_much);
357
358 _M_set_length(length() - __n);
359 }
360
361 template<typename _CharT, typename _Traits, typename _Alloc>
362 _GLIBCXX20_CONSTEXPR
363 void
365 reserve()
366 {
367 if (_M_is_local())
368 return;
369
370 const size_type __length = length();
371 const size_type __capacity = _M_allocated_capacity;
372
373 if (__length <= size_type(_S_local_capacity))
374 {
375 _M_init_local_buf();
376 this->_S_copy(_M_local_buf, _M_data(), __length + 1);
377 _M_destroy(__capacity);
378 _M_data(_M_local_data());
379 }
380#if __cpp_exceptions
381 else if (__length < __capacity)
382 try
383 {
384 pointer __tmp = _S_allocate(_M_get_allocator(), __length + 1);
385 this->_S_copy(__tmp, _M_data(), __length + 1);
386 _M_dispose();
387 _M_data(__tmp);
388 _M_capacity(__length);
389 }
390 catch (const __cxxabiv1::__forced_unwind&)
391 { throw; }
392 catch (...)
393 { /* swallow the exception */ }
394#endif
395 }
396
397 template<typename _CharT, typename _Traits, typename _Alloc>
398 _GLIBCXX20_CONSTEXPR
399 void
401 resize(size_type __n, _CharT __c)
402 {
403 const size_type __size = this->size();
404 if (__size < __n)
405 this->append(__n - __size, __c);
406 else if (__n < __size)
407 this->_M_set_length(__n);
408 }
409
410 template<typename _CharT, typename _Traits, typename _Alloc>
411 _GLIBCXX20_CONSTEXPR
412 basic_string<_CharT, _Traits, _Alloc>&
413 basic_string<_CharT, _Traits, _Alloc>::
414 _M_append(const _CharT* __s, size_type __n)
415 {
416 const size_type __len = __n + this->size();
417
418 if (__len <= this->capacity())
419 {
420 if (__n)
421 this->_S_copy(this->_M_data() + this->size(), __s, __n);
422 }
423 else
424 this->_M_mutate(this->size(), size_type(0), __s, __n);
425
426 this->_M_set_length(__len);
427 return *this;
428 }
429
430 template<typename _CharT, typename _Traits, typename _Alloc>
431 template<typename _InputIterator>
432 _GLIBCXX20_CONSTEXPR
433 basic_string<_CharT, _Traits, _Alloc>&
434 basic_string<_CharT, _Traits, _Alloc>::
435 _M_replace_dispatch(const_iterator __i1, const_iterator __i2,
436 _InputIterator __k1, _InputIterator __k2,
437 std::__false_type)
438 {
439 // _GLIBCXX_RESOLVE_LIB_DEFECTS
440 // 2788. unintentionally require a default constructible allocator
441 const basic_string __s(__k1, __k2, this->get_allocator());
442 const size_type __n1 = __i2 - __i1;
443 return _M_replace(__i1 - begin(), __n1, __s._M_data(),
444 __s.size());
445 }
446
447 template<typename _CharT, typename _Traits, typename _Alloc>
448 _GLIBCXX20_CONSTEXPR
449 basic_string<_CharT, _Traits, _Alloc>&
450 basic_string<_CharT, _Traits, _Alloc>::
451 _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
452 _CharT __c)
453 {
454 _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
455
456 const size_type __old_size = this->size();
457 const size_type __new_size = __old_size + __n2 - __n1;
458
459 if (__new_size <= this->capacity())
460 {
461 pointer __p = this->_M_data() + __pos1;
462
463 const size_type __how_much = __old_size - __pos1 - __n1;
464 if (__how_much && __n1 != __n2)
465 this->_S_move(__p + __n2, __p + __n1, __how_much);
466 }
467 else
468 this->_M_mutate(__pos1, __n1, 0, __n2);
469
470 if (__n2)
471 this->_S_assign(this->_M_data() + __pos1, __n2, __c);
472
473 this->_M_set_length(__new_size);
474 return *this;
475 }
476
477 template<typename _CharT, typename _Traits, typename _Alloc>
478 __attribute__((__noinline__, __noclone__, __cold__)) void
479 basic_string<_CharT, _Traits, _Alloc>::
480 _M_replace_cold(pointer __p, size_type __len1, const _CharT* __s,
481 const size_type __len2, const size_type __how_much)
482 {
483 // Work in-place.
484 if (__len2 && __len2 <= __len1)
485 this->_S_move(__p, __s, __len2);
486 if (__how_much && __len1 != __len2)
487 this->_S_move(__p + __len2, __p + __len1, __how_much);
488 if (__len2 > __len1)
489 {
490 if (__s + __len2 <= __p + __len1)
491 this->_S_move(__p, __s, __len2);
492 else if (__s >= __p + __len1)
493 {
494 // Hint to middle end that __p and __s overlap
495 // (PR 98465).
496 const size_type __poff = (__s - __p) + (__len2 - __len1);
497 this->_S_copy(__p, __p + __poff, __len2);
498 }
499 else
500 {
501 const size_type __nleft = (__p + __len1) - __s;
502 this->_S_move(__p, __s, __nleft);
503 this->_S_copy(__p + __nleft, __p + __len2, __len2 - __nleft);
504 }
505 }
506 }
507
508 template<typename _CharT, typename _Traits, typename _Alloc>
509 _GLIBCXX20_CONSTEXPR
510 basic_string<_CharT, _Traits, _Alloc>&
511 basic_string<_CharT, _Traits, _Alloc>::
512 _M_replace(size_type __pos, size_type __len1, const _CharT* __s,
513 const size_type __len2)
514 {
515 _M_check_length(__len1, __len2, "basic_string::_M_replace");
516
517 const size_type __old_size = this->size();
518 const size_type __new_size = __old_size + __len2 - __len1;
519
520 if (__new_size <= this->capacity())
521 {
522 pointer __p = this->_M_data() + __pos;
523
524 const size_type __how_much = __old_size - __pos - __len1;
525#if __cpp_lib_is_constant_evaluated
527 {
528 auto __newp = _S_allocate(_M_get_allocator(), __new_size);
529 _S_copy(__newp, this->_M_data(), __pos);
530 _S_copy(__newp + __pos, __s, __len2);
531 _S_copy(__newp + __pos + __len2, __p + __len1, __how_much);
532 _S_copy(this->_M_data(), __newp, __new_size);
533 this->_M_get_allocator().deallocate(__newp, __new_size);
534 }
535 else
536#endif
537 if (__builtin_expect(_M_disjunct(__s), true))
538 {
539 if (__how_much && __len1 != __len2)
540 this->_S_move(__p + __len2, __p + __len1, __how_much);
541 if (__len2)
542 this->_S_copy(__p, __s, __len2);
543 }
544 else
545 _M_replace_cold(__p, __len1, __s, __len2, __how_much);
546 }
547 else
548 this->_M_mutate(__pos, __len1, __s, __len2);
549
550 this->_M_set_length(__new_size);
551 return *this;
552 }
553
554 template<typename _CharT, typename _Traits, typename _Alloc>
555 _GLIBCXX20_CONSTEXPR
556 typename basic_string<_CharT, _Traits, _Alloc>::size_type
558 copy(_CharT* __s, size_type __n, size_type __pos) const
559 {
560 _M_check(__pos, "basic_string::copy");
561 __n = _M_limit(__pos, __n);
562 __glibcxx_requires_string_len(__s, __n);
563 if (__n)
564 _S_copy(__s, _M_data() + __pos, __n);
565 // 21.3.5.7 par 3: do not append null. (good.)
566 return __n;
567 }
568
569#if __cplusplus > 202002L
570 template<typename _CharT, typename _Traits, typename _Alloc>
571 template<typename _Operation>
572 constexpr void
573 basic_string<_CharT, _Traits, _Alloc>::
574 resize_and_overwrite(const size_type __n, _Operation __op)
575 {
576 const size_type __capacity = capacity();
577 _CharT* __p;
578 if (__n > __capacity)
579 {
580 auto __new_capacity = __n; // Must not allow _M_create to modify __n.
581 __p = _M_create(__new_capacity, __capacity);
582 this->_S_copy(__p, _M_data(), length()); // exclude trailing null
583#if __cpp_lib_is_constant_evaluated
585 traits_type::assign(__p + length(), __n - length(), _CharT());
586#endif
587 _M_dispose();
588 _M_data(__p);
589 _M_capacity(__new_capacity);
590 }
591 else
592 __p = _M_data();
593 struct _Terminator {
594 constexpr ~_Terminator() { _M_this->_M_set_length(_M_r); }
595 basic_string* _M_this;
596 size_type _M_r;
597 };
598 _Terminator __term{this};
599 auto __r = std::move(__op)(auto(__p), auto(__n));
600 static_assert(ranges::__detail::__is_integer_like<decltype(__r)>);
601 _GLIBCXX_DEBUG_ASSERT(__r >= 0 && __r <= __n);
602 __term._M_r = size_type(__r);
603 if (__term._M_r > __n)
604 __builtin_unreachable();
605 }
606#endif // C++23
607
608#endif // _GLIBCXX_USE_CXX11_ABI
609
610#if __cpp_lib_constexpr_string >= 201907L
611# define _GLIBCXX_STRING_CONSTEXPR constexpr
612#else
613# define _GLIBCXX_STRING_CONSTEXPR
614#endif
615 template<typename _CharT, typename _Traits, typename _Alloc>
616 _GLIBCXX_STRING_CONSTEXPR
617 typename basic_string<_CharT, _Traits, _Alloc>::size_type
619 find(const _CharT* __s, size_type __pos, size_type __n) const
620 _GLIBCXX_NOEXCEPT
621 {
622 __glibcxx_requires_string_len(__s, __n);
623 const size_type __size = this->size();
624
625 if (__n == 0)
626 return __pos <= __size ? __pos : npos;
627 if (__pos >= __size)
628 return npos;
629
630 const _CharT __elem0 = __s[0];
631 const _CharT* const __data = data();
632 const _CharT* __first = __data + __pos;
633 const _CharT* const __last = __data + __size;
634 size_type __len = __size - __pos;
635
636 while (__len >= __n)
637 {
638 // Find the first occurrence of __elem0:
639 __first = traits_type::find(__first, __len - __n + 1, __elem0);
640 if (!__first)
641 return npos;
642 // Compare the full strings from the first occurrence of __elem0.
643 // We already know that __first[0] == __s[0] but compare them again
644 // anyway because __s is probably aligned, which helps memcmp.
645 if (traits_type::compare(__first, __s, __n) == 0)
646 return __first - __data;
647 __len = __last - ++__first;
648 }
649 return npos;
650 }
651
652 template<typename _CharT, typename _Traits, typename _Alloc>
653 _GLIBCXX_STRING_CONSTEXPR
654 typename basic_string<_CharT, _Traits, _Alloc>::size_type
656 find(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
657 {
658 size_type __ret = npos;
659 const size_type __size = this->size();
660 if (__pos < __size)
661 {
662 const _CharT* __data = _M_data();
663 const size_type __n = __size - __pos;
664 const _CharT* __p = traits_type::find(__data + __pos, __n, __c);
665 if (__p)
666 __ret = __p - __data;
667 }
668 return __ret;
669 }
670
671 template<typename _CharT, typename _Traits, typename _Alloc>
672 _GLIBCXX_STRING_CONSTEXPR
673 typename basic_string<_CharT, _Traits, _Alloc>::size_type
675 rfind(const _CharT* __s, size_type __pos, size_type __n) const
676 _GLIBCXX_NOEXCEPT
677 {
678 __glibcxx_requires_string_len(__s, __n);
679 const size_type __size = this->size();
680 if (__n <= __size)
681 {
682 __pos = std::min(size_type(__size - __n), __pos);
683 const _CharT* __data = _M_data();
684 do
685 {
686 if (traits_type::compare(__data + __pos, __s, __n) == 0)
687 return __pos;
688 }
689 while (__pos-- > 0);
690 }
691 return npos;
692 }
693
694 template<typename _CharT, typename _Traits, typename _Alloc>
695 _GLIBCXX_STRING_CONSTEXPR
696 typename basic_string<_CharT, _Traits, _Alloc>::size_type
698 rfind(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
699 {
700 size_type __size = this->size();
701 if (__size)
702 {
703 if (--__size > __pos)
704 __size = __pos;
705 for (++__size; __size-- > 0; )
706 if (traits_type::eq(_M_data()[__size], __c))
707 return __size;
708 }
709 return npos;
710 }
711
712 template<typename _CharT, typename _Traits, typename _Alloc>
713 _GLIBCXX_STRING_CONSTEXPR
714 typename basic_string<_CharT, _Traits, _Alloc>::size_type
716 find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
717 _GLIBCXX_NOEXCEPT
718 {
719 __glibcxx_requires_string_len(__s, __n);
720 for (; __n && __pos < this->size(); ++__pos)
721 {
722 const _CharT* __p = traits_type::find(__s, __n, _M_data()[__pos]);
723 if (__p)
724 return __pos;
725 }
726 return npos;
727 }
728
729 template<typename _CharT, typename _Traits, typename _Alloc>
730 _GLIBCXX_STRING_CONSTEXPR
731 typename basic_string<_CharT, _Traits, _Alloc>::size_type
733 find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
734 _GLIBCXX_NOEXCEPT
735 {
736 __glibcxx_requires_string_len(__s, __n);
737 size_type __size = this->size();
738 if (__size && __n)
739 {
740 if (--__size > __pos)
741 __size = __pos;
742 do
743 {
744 if (traits_type::find(__s, __n, _M_data()[__size]))
745 return __size;
746 }
747 while (__size-- != 0);
748 }
749 return npos;
750 }
751
752 template<typename _CharT, typename _Traits, typename _Alloc>
753 _GLIBCXX_STRING_CONSTEXPR
754 typename basic_string<_CharT, _Traits, _Alloc>::size_type
756 find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
757 _GLIBCXX_NOEXCEPT
758 {
759 __glibcxx_requires_string_len(__s, __n);
760 for (; __pos < this->size(); ++__pos)
761 if (!traits_type::find(__s, __n, _M_data()[__pos]))
762 return __pos;
763 return npos;
764 }
765
766 template<typename _CharT, typename _Traits, typename _Alloc>
767 _GLIBCXX_STRING_CONSTEXPR
768 typename basic_string<_CharT, _Traits, _Alloc>::size_type
770 find_first_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
771 {
772 for (; __pos < this->size(); ++__pos)
773 if (!traits_type::eq(_M_data()[__pos], __c))
774 return __pos;
775 return npos;
776 }
777
778 template<typename _CharT, typename _Traits, typename _Alloc>
779 _GLIBCXX_STRING_CONSTEXPR
780 typename basic_string<_CharT, _Traits, _Alloc>::size_type
782 find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
783 _GLIBCXX_NOEXCEPT
784 {
785 __glibcxx_requires_string_len(__s, __n);
786 size_type __size = this->size();
787 if (__size)
788 {
789 if (--__size > __pos)
790 __size = __pos;
791 do
792 {
793 if (!traits_type::find(__s, __n, _M_data()[__size]))
794 return __size;
795 }
796 while (__size--);
797 }
798 return npos;
799 }
800
801 template<typename _CharT, typename _Traits, typename _Alloc>
802 _GLIBCXX_STRING_CONSTEXPR
803 typename basic_string<_CharT, _Traits, _Alloc>::size_type
805 find_last_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
806 {
807 size_type __size = this->size();
808 if (__size)
809 {
810 if (--__size > __pos)
811 __size = __pos;
812 do
813 {
814 if (!traits_type::eq(_M_data()[__size], __c))
815 return __size;
816 }
817 while (__size--);
818 }
819 return npos;
820 }
821
822#undef _GLIBCXX_STRING_CONSTEXPR
823
824 // 21.3.7.9 basic_string::getline and operators
825 template<typename _CharT, typename _Traits, typename _Alloc>
829 {
830 typedef basic_istream<_CharT, _Traits> __istream_type;
831 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
832 typedef typename __istream_type::ios_base __ios_base;
833 typedef typename __istream_type::int_type __int_type;
834 typedef typename __string_type::size_type __size_type;
835 typedef ctype<_CharT> __ctype_type;
836 typedef typename __ctype_type::ctype_base __ctype_base;
837
838 __size_type __extracted = 0;
839 typename __ios_base::iostate __err = __ios_base::goodbit;
840 typename __istream_type::sentry __cerb(__in, false);
841 if (__cerb)
842 {
843 __try
844 {
845 // Avoid reallocation for common case.
846 __str.erase();
847 _CharT __buf[128];
848 __size_type __len = 0;
849 const streamsize __w = __in.width();
850 const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
851 : __str.max_size();
852 const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
853 const __int_type __eof = _Traits::eof();
854 __int_type __c = __in.rdbuf()->sgetc();
855
856 while (__extracted < __n
857 && !_Traits::eq_int_type(__c, __eof)
858 && !__ct.is(__ctype_base::space,
859 _Traits::to_char_type(__c)))
860 {
861 if (__len == sizeof(__buf) / sizeof(_CharT))
862 {
863 __str.append(__buf, sizeof(__buf) / sizeof(_CharT));
864 __len = 0;
865 }
866 __buf[__len++] = _Traits::to_char_type(__c);
867 ++__extracted;
868 __c = __in.rdbuf()->snextc();
869 }
870 __str.append(__buf, __len);
871
872 if (__extracted < __n && _Traits::eq_int_type(__c, __eof))
873 __err |= __ios_base::eofbit;
874 __in.width(0);
875 }
877 {
878 __in._M_setstate(__ios_base::badbit);
879 __throw_exception_again;
880 }
881 __catch(...)
882 {
883 // _GLIBCXX_RESOLVE_LIB_DEFECTS
884 // 91. Description of operator>> and getline() for string<>
885 // might cause endless loop
886 __in._M_setstate(__ios_base::badbit);
887 }
888 }
889 // 211. operator>>(istream&, string&) doesn't set failbit
890 if (!__extracted)
891 __err |= __ios_base::failbit;
892 if (__err)
893 __in.setstate(__err);
894 return __in;
895 }
896
897 template<typename _CharT, typename _Traits, typename _Alloc>
898 basic_istream<_CharT, _Traits>&
900 basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
901 {
902 typedef basic_istream<_CharT, _Traits> __istream_type;
903 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
904 typedef typename __istream_type::ios_base __ios_base;
905 typedef typename __istream_type::int_type __int_type;
906 typedef typename __string_type::size_type __size_type;
907
908 __size_type __extracted = 0;
909 const __size_type __n = __str.max_size();
910 typename __ios_base::iostate __err = __ios_base::goodbit;
911 typename __istream_type::sentry __cerb(__in, true);
912 if (__cerb)
913 {
914 __try
915 {
916 __str.erase();
917 const __int_type __idelim = _Traits::to_int_type(__delim);
918 const __int_type __eof = _Traits::eof();
919 __int_type __c = __in.rdbuf()->sgetc();
920
921 while (__extracted < __n
922 && !_Traits::eq_int_type(__c, __eof)
923 && !_Traits::eq_int_type(__c, __idelim))
924 {
925 __str += _Traits::to_char_type(__c);
926 ++__extracted;
927 __c = __in.rdbuf()->snextc();
928 }
929
930 if (_Traits::eq_int_type(__c, __eof))
931 __err |= __ios_base::eofbit;
932 else if (_Traits::eq_int_type(__c, __idelim))
933 {
934 ++__extracted;
935 __in.rdbuf()->sbumpc();
936 }
937 else
938 __err |= __ios_base::failbit;
939 }
941 {
942 __in._M_setstate(__ios_base::badbit);
943 __throw_exception_again;
944 }
945 __catch(...)
946 {
947 // _GLIBCXX_RESOLVE_LIB_DEFECTS
948 // 91. Description of operator>> and getline() for string<>
949 // might cause endless loop
950 __in._M_setstate(__ios_base::badbit);
951 }
952 }
953 if (!__extracted)
954 __err |= __ios_base::failbit;
955 if (__err)
956 __in.setstate(__err);
957 return __in;
958 }
959
960 // Inhibit implicit instantiations for required instantiations,
961 // which are defined via explicit instantiations elsewhere.
962#if _GLIBCXX_EXTERN_TEMPLATE
963 // The explicit instantiation definitions in src/c++11/string-inst.cc and
964 // src/c++17/string-inst.cc only instantiate the members required for C++17
965 // and earlier standards (so not C++20's starts_with and ends_with).
966 // Suppress the explicit instantiation declarations for C++20, so C++20
967 // code will implicitly instantiate std::string and std::wstring as needed.
968# if __cplusplus <= 201703L && _GLIBCXX_EXTERN_TEMPLATE > 0
969 extern template class basic_string<char>;
970# elif ! _GLIBCXX_USE_CXX11_ABI
971 // Still need to prevent implicit instantiation of the COW empty rep,
972 // to ensure the definition in libstdc++.so is unique (PR 86138).
973 extern template basic_string<char>::size_type
974 basic_string<char>::_Rep::_S_empty_rep_storage[];
975# elif _GLIBCXX_EXTERN_TEMPLATE > 0
976 // Export _M_replace_cold even for C++20.
977 extern template void
978 basic_string<char>::_M_replace_cold(char *, size_type, const char*,
979 const size_type, const size_type);
980# endif
981
982 extern template
983 basic_istream<char>&
984 operator>>(basic_istream<char>&, string&);
985 extern template
986 basic_ostream<char>&
987 operator<<(basic_ostream<char>&, const string&);
988 extern template
989 basic_istream<char>&
990 getline(basic_istream<char>&, string&, char);
991 extern template
992 basic_istream<char>&
993 getline(basic_istream<char>&, string&);
994
995#ifdef _GLIBCXX_USE_WCHAR_T
996# if __cplusplus <= 201703L && _GLIBCXX_EXTERN_TEMPLATE > 0
997 extern template class basic_string<wchar_t>;
998# elif ! _GLIBCXX_USE_CXX11_ABI
999 extern template basic_string<wchar_t>::size_type
1000 basic_string<wchar_t>::_Rep::_S_empty_rep_storage[];
1001# elif _GLIBCXX_EXTERN_TEMPLATE > 0
1002 // Export _M_replace_cold even for C++20.
1003 extern template void
1004 basic_string<wchar_t>::_M_replace_cold(wchar_t*, size_type, const wchar_t*,
1005 const size_type, const size_type);
1006# endif
1007
1008 extern template
1009 basic_istream<wchar_t>&
1010 operator>>(basic_istream<wchar_t>&, wstring&);
1011 extern template
1012 basic_ostream<wchar_t>&
1013 operator<<(basic_ostream<wchar_t>&, const wstring&);
1014 extern template
1015 basic_istream<wchar_t>&
1016 getline(basic_istream<wchar_t>&, wstring&, wchar_t);
1017 extern template
1018 basic_istream<wchar_t>&
1019 getline(basic_istream<wchar_t>&, wstring&);
1020#endif // _GLIBCXX_USE_WCHAR_T
1021#endif // _GLIBCXX_EXTERN_TEMPLATE
1022
1023_GLIBCXX_END_NAMESPACE_VERSION
1024} // namespace std
1025
1026#endif
constexpr bool is_constant_evaluated() noexcept
Returns true only when called during constant evaluation.
Definition: type_traits:3649
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition: move.h:97
constexpr _Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
Definition: move.h:51
_Tp * begin(valarray< _Tp > &__va) noexcept
Return an iterator pointing to the first element of the valarray.
Definition: valarray:1227
constexpr const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:233
basic_string< wchar_t > wstring
A string of wchar_t.
Definition: stringfwd.h:80
ISO C++ entities toplevel namespace is std.
ptrdiff_t streamsize
Integral type for I/O operation counts and buffer sizes.
Definition: postypes.h:68
basic_istream< _CharT, _Traits > & getline(basic_istream< _CharT, _Traits > &__is, basic_string< _CharT, _Traits, _Alloc > &__str, _CharT __delim)
Read a line from stream into a string.
constexpr iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
constexpr auto size(const _Container &__cont) noexcept(noexcept(__cont.size())) -> decltype(__cont.size())
Return the size of a container.
Definition: range_access.h:264
std::basic_istream< _CharT, _Traits > & operator>>(std::basic_istream< _CharT, _Traits > &__is, bitset< _Nb > &__x)
Global I/O operators for bitsets.
Definition: bitset:1593
std::basic_ostream< _CharT, _Traits > & operator<<(std::basic_ostream< _CharT, _Traits > &__os, const bitset< _Nb > &__x)
Global I/O operators for bitsets.
Definition: bitset:1683
constexpr auto data(_Container &__cont) noexcept(noexcept(__cont.data())) -> decltype(__cont.data())
Return the data pointer of a container.
Definition: range_access.h:314
void setstate(iostate __state)
Sets additional flags in the error state.
Definition: basic_ios.h:157
basic_streambuf< _CharT, _Traits > * rdbuf() const
Accessing the underlying buffer.
Definition: basic_ios.h:321
Template class basic_istream.
Definition: istream:61
Managing sequences of characters and character-like objects.
Definition: cow_string.h:117
void swap(basic_string &__s) noexcept(/*conditional */)
Swap contents with another string.
Definition: cow_string.h:3513
size_type find_first_of(const basic_string &__str, size_type __pos=0) const noexcept
Find position of a character of string.
Definition: cow_string.h:2420
size_type find(const _CharT *__s, size_type __pos, size_type __n) const noexcept
Find position of a C substring.
size_type find_last_not_of(const basic_string &__str, size_type __pos=npos) const noexcept
Find last position of a character not in string.
Definition: cow_string.h:2669
size_type find_first_not_of(const basic_string &__str, size_type __pos=0) const noexcept
Find position of a character not in string.
Definition: cow_string.h:2587
size_type copy(_CharT *__s, size_type __n, size_type __pos=0) const
Copy substring into C string.
Definition: cow_string.h:3709
size_type find_last_of(const basic_string &__str, size_type __pos=npos) const noexcept
Find last position of a character of string.
Definition: cow_string.h:2504
size_type rfind(const basic_string &__str, size_type __pos=npos) const noexcept
Find last position of a string.
Definition: cow_string.h:2341
void resize(size_type __n, _CharT __c)
Resizes the string to the specified number of characters.
Definition: cow_string.h:3635
void reserve()
Equivalent to shrink_to_fit().
Definition: cow_string.h:3688
basic_string & append(const basic_string &__str)
Append a string to this string.
Definition: cow_string.h:3307
static const size_type npos
Value returned by various member functions when they fail.
Definition: cow_string.h:330
size_type max_size() const noexcept
Returns the size() of the largest possible string.
Definition: cow_string.h:933
basic_string & erase(size_type __pos=0, size_type __n=npos)
Remove characters.
Definition: cow_string.h:1718
Thrown as part of forced unwinding.
Definition: cxxabi_forced.h:49
streamsize width() const
Flags access.
Definition: ios_base.h:755
locale getloc() const
Locale access.
Definition: ios_base.h:806
Primary class template ctype facet.
Marking input iterators.
Forward iterators support a superset of input iterator operations.